Thank you for posting such a heartfelt story. I applaud you for being so self actualized and working on your recovery. It took strength on your part to get to this point.
I have had my own experiences with both amphetamines and alcohol and have been sober for several years now. My journey sounded a lot like your's with experimentation, highs and lows.
Please know that recovery is an ongoing process and you are stronger than you think. A drink after a stressful day isn't the end of the world and it gave you an awareness of what you might not want to do during the next stress. Try to focus on what you have, where you want to go and who you want to be. I found that when I focused on gratitude and growth there wasn't much 'thought time' left to focus on fear of what might happen and regret over the past.
I'm also new to this form and when I read your story, it made me think of myself when I was younger. Thank you again for posting.